RADIO BASE STATION, USER TERMINAL, RADIO COMMUNICATION SYSTEM AND RADIO COMMUNICATION METHOD

摘要

The present invention is designed to reduce the increase in the amount of the calculation process in a mobile station and the amount of CSI feedback data, and also prevent the amount of overall system capacity from decreasing. This radio communication system (1) has a radio base station (200) which can form a plurality of beams that are vertically sectorized. The radio base station (200), using an array antenna (10), forms at least the first beam that is directed to the cell edge side and a second beam that is directed to the cell center side, in parallel. A mobile station (100) measures channel quality by extracting reference signals from each of the first beam and the second beam, generates a communication quality feedback signal including channel quality measured from at least one of the beams, and feeds this back to the radio base station (200) via the uplink.

主权项

1. A radio communication system comprising a radio base station that forms a cell and a user terminal that establishes wireless connection with the radio base station, wherein:
the radio base station comprises:
an array antenna that has a plurality of antenna elements aligned in one direction, the plurality of antenna elements being divided into a plurality of groups in the direction of the alignment of the elements;a precoding multiplication section configured to multiply signals to supply to the antenna elements, by each weight of precoding weights, per antenna element group;a precoding weight section configured to generate precoding weights by which the array antenna forms at least a first beam that is directed to a cell edge side and a second beam that is directed to a cell center side in parallel; anda mapping section configured to arrange different reference signals allocated respectively to the first beam and the second beam, in separate resources; the user terminal comprises:
a receiving section configured to receive the first beam and the second beam;a channel quality measurement section configured to extract the reference signals from each of the received first beam and second beam and measure channel quality;a feedback signal generating section configured to generate a communication quality feedback signal that includes the channel quality measured from at least one of the first and second beams; anda transmission section configured to feed back the generated communication quality feedback signal to the radio base station via an uplink.